colint50 wrote:He has already purchased 4 x 190w solar panels - specs CEEG model SST SE 190-72M, Pmax 190w, 5.08 Amps, Open cct volts 44.48v, SL open cut current 5.42A
He would require a MPPT, inverter and batteries plus the option of utilising a generator for charging batteries if required in overcast weather periods.
If going 12V then you need to understand that the panels will be 4 in parallel, so will require fusing for each panel preferably in both the positive and the negative leads. Rating MAX 12A the fuses are there so that should a single panel develop an issue (short circuit for instance) and start accepting current rather providing it then the fuse/s will "blow" rather than the panel having a total meltdown (fire).
colint50 wrote:My thinking was to go with 12v lighting, MPPT 20A unit, inverter 1500w, batteries say 4 x 120ah, given that panels total 760W.
A true MPPT charge controller will need to be 60A for 12V with 760Watts of panels and if the panels are set-up properly, under various circumstances it will be able to produce this sort of current. Proper MPPT charge controllers that handle this sort of current are in excess of $300.00 at the very least, elcheapos while they may say they are MPPT they most certainly are not.
A decent inverter preferably a pure sine wave LF (Low Frequency) inverter are by far the best option. Check the efficiency of the unit.
N.B. Pass though or Bypass efficiency or similar is a rubbish spec %, ignore it as the inverter is not actually providing power in that mode, you want the actual inverter efficiency and not the eco mode either.